1. Field of the Invention (Technical Field)
The present invention relates to internal combustion engine exhaust gas recirculation (EGR), particularly to an EGR mixer apparatus for maximizing EGR rates and lowering emission levels.
2. Description of Related Art
Note that the where the following discussion refers to a number of publications by author(s) and year of publication, due to recent publication dates certain publications are not to be considered as prior art vis-a-vis the present invention. Discussion of such publications herein is given for more complete background and is not to be construed as an admission that such publications are prior art for patentability determination purposes.
In the reduction of NOx emissions by turbocharged internal combustion engines, exhaust as recirculation (“EGR”) such as long route EGR systems (“LREGR”) (also known as low pressure loop or long path EGR systems) take exhaust gas from a point downstream of the exhaust of the turbocharger exhaust turbine to the turbocharger compressor and on to the intake manifold of the engine. The exhaust gas is typically mixed with fresh air in an EGR mixer prior to introduction into the intake manifold.
The flow characteristics of exhaust gas as it enters and moves through the EGR mixer affect the efficiency of the mixing of the exhaust gas with ambient air, and therefore the effectiveness of the reduction of emissions. Therefore, there is a need for an EGR mixer that improves the mixing of exhaust gas with ambient air.